Suspension of disbelief not withstanding, that's why I can't believe Raven is capable shapeshift into a biological XY male and back to an XX female on a whim under any circumstance. Theoretically, if Raven could randomly change any aspect of her DNA she would not be Mystique anymore.
CHROMOSOME:
updated: August 18, 2023
Chromosomes are threadlike structures made of protein and a single molecule of DNA that serve to carry the genomic information from cell to cell. In plants and animals (including humans), chromosomes reside in the nucleus of cells. Humans have 22 pairs of numbered chromosomes (autosomes) and one pair of sex chromosomes (XX or XY), for a total of 46.